Some embodiments described herein relate generally to data flow in a network system and, in particular, to the dynamic and automatic maintenance of a layer-3 integrated routing and bridging (IRB) interface within a network segment, such as a virtual local area network (VLAN), of a distributed network system.
Some known networking systems control an IRB interface by local state machines based on corresponding layer-2 interfaces on any router/switch. To keep the IRB interface active, at least one layer-2 interface of the corresponding VLAN typically remains active on a given router or switch. In the case of a switch fabric system that is a distributed network, however, VLANs can span multiple nodes (distributed VLANs) including the node that is enabled for routing and supports layer-3 protocols. This designated node may or may not have the corresponding layer-2 interface that is used to keep up the IRB interface. In such cases, the IRB interface may be inactivated because of no layer-2 interface or an inactive layer-2 interface on the designated VLAN node. This can prevent any routes to be advertised on routing protocols and can prevent peripheral devices like servers or workstations to be connected to the core network. Accordingly, such networking systems do not operate as efficiently as possible.
Accordingly, a need exists for network segments within a networking system to have IRB interfaces or Layer 3 switch interfaces that are based on flood routes associated with all the nodes in a distributed VLAN, and that can be dynamically configured based on the processing needs of the networking system. Such IRB interfaces may or may not have underlying layer-2 interfaces on physical devices within the network segment, but will still be maintained in the “up” or “active” state based on the flood routes.